| Manual grinding has the labor force,the poor environment,the dust is harmful to human health,and the labor difficulties,etc.,this defects that brings the robot has a very realistic need to replace the manual grinding operation.At present,robots are capable of performing sanding tasks with simple surface shapes and low requirements,but it is difficult for robots to replace manual operations in the face of complex surfaces,uneven margins,and high surface quality requirements.This paper studies key issues such as path planning,complex surface fitting,and grinding contact force control.(1)Analysis of grinding power.Taking the plane grinding operation as the object,the research results and empirical formulas of the grinding wheel are comprehensively analyzed,the composition of the grinding under the grinding condition of the sandpaper is analyzed,the formula of the grinding force is derived,the force state diagram of the sanding paper is drawn,and the sanding paper is obtained.The characteristics of the operation provide a theoretical basis for the development of robot polishing tools.(2)Flexible device design for flexible,multi-environment applications.In this,grinding process is studied,grinding path planning and grinding attitude control are analyzed,and a curve fitting method based on NURBS(non-uniform rational B-spline curve)is proposed.Combining with the characteristics of this design,grinding path and grinding point planning are carried out.On the basis of grinding process analysis,based on flexibility,multi-environment application and low-cost design concept,it meets the requirements of normal force output design and improves the control precision of compliant device.Three guiding devices are designed,and force sensor and displacement sensor are installed for miniaturization and flexible operation.And provide a basis for stable control.(3)The establishment of a passive and smooth grinding force balance equation.Passive and smooth grinding contact force control research begins with the general universal sanding force analysis,and establishes the force balance equation in the case of surface grinding,and obtains the general universal transfer function equation.Then according to the actual situation of the grinding force output designed in this paper,the transfer function equation used in this design is studied.The Bird diagram and Nyquist diagram are drawn by Matlab statement,and the stability of the transfer function is analyzed.Finally.Matlab/Simulink is used in simulation,applying step input signal and sinusoidal input signal,analyzing the response curve,and obtaining the feasibility of passive compliance grinding contact force control.The purpose of passive compliant smoothing contact force control research is mainly to compare and analyze the results with the active compliant grinding contact force control in the latter chapter.(4)Simulation analysis of contact force of active and smooth grinding operations based on fuzzy PID control algorithm.The active and smooth grinding method uses the cylinder drive.The balance equation is established by force analysis,the transfer function is obtained,and the stability analysis of the transfer function is performed.The traditional PID control is analyzed and compared with the fuzzy PID control.(5)Complex surface fitting method for arc approximation algorithm.The NURBS non-uniform rational B-spline curve is a curved surface model defined by a piecewise rational polynomial.The arc approximation algorithm is used to fit the complex curve and surface,and the feature extraction of complex surface data can be realized. |
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